The present invention pertains to an environmental control system to provide a healthful enclosed environment for people living, working, travelling, or otherwise spending time in an enclosed structure. The environmental control system enables people to avoid temperature extremes, undesirable humidity levels, polluted air, sudden variations in barometric pressure, and other conditions which are detrimental to the health and well being of the inhabitants.
Many people desire or require a healthful, controlled environment in which to live, work, travel, and engage in leisure activities. This is particularly true of older people and of people having health problems such as allergies, respiratory problems, circulatory problems, arthritis, or rheumatism. As recognized in, for example, The Columbia University College of Physicians and Surgeons Complete Home Medical Guide, Donald F. Tapley, M.D., editor, 1988, indoor air pollutants include ozone, carbon oxides, nitrous oxide, formaldehyde, and aerosol propellants, all of which have been found to cause health problems. The problems many people experience from allergies are well known. The "Cover Story" titled "Now's a very hopeful time for sufferers" found at page 1A of the May 9, 1990 USA Today describes such problems and the efforts made to avoid or overcome them.
It is a common practice to control the temperature and humidity of the air within an enclosed structure and to provide a mechanical or an electronic filter to remove pollen and particulates from the air. However, other impurities also are frequently found in the air. By way of example, as reported in "Indoor Ozone Exposures," by Charles J. Weschler, Helen C. Shields, and Datta V. Noik, The Journal of the Air & Waste Management Association, volume 39, No. 12, Dec. 1989, pages 1562-1568, studies have found that for many people indoor ozone exposure (i.e. concentration times duration of exposure) is greater than outdoor ozone exposure Undesirable levels of nitrogen oxides are also sometimes encountered inside buildings and other enclosed structures. Thus, it is desirable to reduce or control these and other forms of pollution from the air. Further, such humidity control has generally not provided optimum humidity levels for extended periods of time over varying temperatures. Medical experience indicates, for example, that a majority of the persons suffering from arthritis have less discomfort if they are able to remain for extended periods of time in an atmosphere with a humidity level in the range of from about 35% to about 55%.